Air conditioning apparatus



FEE). 1, 1938. Nl H, GAY 2,107,243

AIR CONDITIONING APPARATUS Filed Aug. l5, 1955 t E N Inventor: JV'ornan/E. 6165/,

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Patented Feb. 1, 1938 AIR. CONDITIONING APPARATUS Norman H. Gay, LosAngeles, Calif.

Application August 15,

7 Claims.

This invention relates to improvements `in airconditioning apparatus,and particularly concerns means for removing humidity from the air whileit is being circulated to and from the apartment.

One of the features of the present invention is the provision of devicesoperating to provide a circulation of a heat-exchanging medium which isemployed for pre-cooling the air preparatory to a secondary coolingoperation, and for reheating the air following such secondary coolingthereof.

Another feature of the present invention is the provision of arefrigerating plant for establishing a cooling effect upon the air, andcomprising an evaporator disposed in the path of the air movement, inconjunction with a condenser for the refrigerant gas and means forraising the gas upon its return from the evaporator to a suitablepressure, together with means located in the conduit from the condenserto the evaporator for producing a sub-,cooling eifectupon the liquid andthereby producing a heating effect upon the air.

Another feature of the present invention is the provision of arefrigerating plant including an evaporator and a conduit leading fromthe evaporator to pressure producing means, this conduit includingdevices located in the path of the air movement for causing a cooling ofthesair on its way to the evaporator for a further cooling at saidevaporator.

A further feature of the present invention is the provision of arefrigerating plant including an evaporator for producing-a cooling ofthe air to a pre-determinedminmum temperature, together with meanstraversed by the refrigerant medium on its way from and to theevaporator for effecting a pre-cooling and an after-heating of the air.

A still further feature of the present invention is the provision of arefrigerating plant including an evaporator disposed in the path oftheair movement, means associated with arefrigerating plant for producing apre-cooling and an afterheating of the circulating air, and further heatexchange devices for eifecting a pre-cooling and an' after-heating.independently of the refrigerating plant.

'Still another feature of the present invention is theprovision of meansfor employing a supply of cool Water in multiple flow for eifecting thecondensation of refrigerant gas in the condenser, of the aforesaidrefrigerating plant and for pro- 1935, Serial No. 36,396

ducing a first or initial pre-cooling of the air on its way to theevaporator surfaces.

Still another feature of the present invention is the provision of suchair-conditioning apparatus in conjunction with automatic control de- 5vices for determining the rate of heat exchange between the pre-coolingand the after-heating devices.

With these and other features as objects in view, as will appear moreclearly inthe course of the following specification and claims, anillustrative form of practicing the invention is set out on theaccompanying drawing, which conventionally and diagrammatically showselements of construction and their assemblage according to the presentinvention. v

In the drawing, the apartment Il), for which the air is to beconditioned, is connected by an outlet duct II, with a conduit I2 whichin the illustrative apparatus is formed as a structure enclosing thevarious cooling, heating and eliminating devices which are interposed inthe path of flow of the circulating air. After passing through thesedevices, the air is moved by a fan I3, driven by the motor I4, throughan admission duct I5 back into the apartment I0, thus establishing thecirculation of air.

A refrigerating plant is illustrated as comprising a compressor orcompressors I6 capable of variable action for delivering definitequantities of hot compressed refrigerant gas, according to itsadjustment.- This compressed gas passes into a condenser I1 in which itis liquefied and moves to a sub-cooler I8 for the refrigerant liquid,this subcooler having its heat exchanging Walls disposed in the path ofthe owof air through the conduit I2 so that the hot refrigerant liquidis cooled by the air on its way through the conduit I2 back to theapartment I0, and conversely the heat from this liquid is employed forwarming the air. The cooled liquid now passes to the expansion valve I9and thence into the evaporator 20 which likewise has heat-exchange Wallsdisposed in the path of the air moving through the conduit I2, so thatthis evaporator operates to produce a predetermined minimum temperatureof this air. From the evaporator 20, the refrigerant gas escapes andpasses through a superheater 2| on its way back to the compressor I6.This superheater 2Ifis likewise disposed in heat exchange relationshipwith the air flowing through the conduit I2, so that this air isprecooled before it passes into the evaporator 20 on the one hand, andon the other hand the refrigerant gas is superheated and all liquidcontent thereof is volatilized before passing to the compressor I6. Itwill be noted that this establishes a refrigerating plant with theseveral parts connected for performing multiple operations upon the air.during its passage in the conduit I2.

The condenser I1 is illustrated as being controlled by cold water comingfrom a source of supply by a conduit 22, and which is utilized undercontrol of the valve 23 in a spray device 24, by which the water iscaused to flow over the condenser I1. The water from the condenser iscaught in a sump 25 and then passes to a discharge or waste passage 26.A branch of this cold Water supply pipe 22 also communicates with avalve 21 so that cold water may also be passed through a. precooler 28comprising a coil, for example, traversed by this cold water, whichescapes from the cooler 28 into the waste pipe 25.

A further heat exchange system, independent of the refrigerating plant,is shown as comprising a circulating pump 36 for moving the exchangemedium, which is preferably water or brine by reason of the large heatcapacity of aqueous fluids. This heat exchange medium passes by conduit3| into the heat exchanger 32 where the Warm water causes a Warming ofthe air passing through conduit I2, and is itself cooled. The cooledwater passes by conduit 33 into the heat exchanger 34 where it serves tocool the airon its way to the evaporator 20, and is itself warmedthereby, so that warm water returns by conduit 35 to the pump 30.

The operation of the precooling devices 28, 2|, and 34 causes asuccessive reduction of the temperature of the air, and this is finallybrought to a predetermined minimum by the operation of evaporator 20. Asa result, the circulating air is reduced to a temperature below its dewpoint so that water precipitates therefrom and forms suspended globulesand also collects on the walls of conduit I2 and of the devicesthemselves and iiows down and is discharged. The suspended globules areremoved from the air current by an eliminator 36 which is shownconventionally. Thereafter, the cold dry air is successively heated bythe devices 32 and I8. If a suilicient heating is not afforded thereby,a higher temperature is produced by the radiator device 31 which issupplied through a control valve 38 with steam coming from a steam main39. This steam valve 38 is actuated by a thermostatic device 40 which iscontrolled through conduit 4I from the thermostat 42.

As it is usually desirable to permit the escape of a portion of thecirculating air, and to replace this portion by an admission of freshair, an exhaust duct 43 may be utilized in conjunction with theregulator damper 44, while fresh air is admitted through a duct 45 undercontrol of a damper 46. 'Ihe two dampers may be coordinated' in theiraction as by a connecting link 41.

It ispreferred to provide a type of automatic control for the apparatus.form, a hygrostat is connected by conduit 5I with the driving device 52which turns a shaft upon which are mounted the contact sectors 53, 54,55, and 56. These contact sectors have varying angles and cooperaterespectively with the brushes 51, 58, 59, and 60. Current is suppliedfrom a main conductor 6I through a switch 62 to conductor 63 and thus tothe brush 51 which remains in contact with the sector 53 regardless ofthe position of the several sectors. Sector 53 is electrically connectedto all ot the other 'sec- In the illustrated tors so that current iscontinuously supplied thereto so long as switch 62 is closed. When ,thehygrostat 50 indicates an extremely dry condition, the brush 58 does notengage the sector 54, and brushes 59 and 6I) are likewise free of theirsectors and 56. The operation of the plant is now essentiallystatic, andcomprises a circulation of air by the fan I3.

When the moisture content of the air increases above the desiredpercentage, the hygrostat 50 causes such a movement of the4 sectors thatcurrent flows from sector 54 by brush 58 and conductor 64 to thecirculating pump 3l) and starts this pump. If the refrigerating systemis entirely static, no result occurs, but if the evaporator is stillcool from a prior refrigerating cycle, the air issuing from it cools theheat exchanger 32 and thus a cooling is effected at the heat exchanger34 and thus a slightly greater cooling is effected of the volume of aircirculating through the conduit I2 and a slight elimination of moistureoccurs therefrom.

If this does not suffice and the hygrostat v5l) continues to indicate anexcessive moisture, a Contact is established by the further rotation ofthe sectors so that sector 55 causes current to flowto brush 59 and byconductor 66 to the control device 61 of the compressor I6 and thelatter comes into operation for compression at a fraction of its maximumcapacity, and thus the refrigerant plant as a whole comes into actionand the evaporator 20 passes to a lower temperature, below the dewpointof the air moving through conduit I2, and moisture is eliminatedtherefrom. During this phase of the cycle, it will be noted that therefrigerant medium is employed at sub-cooler I8 for warming the air onits way back to the apartment I9, that it is employed in the evaporator20 for producing the minimum temperature of circulating air, land thatthe returning quasi-gaseous or gaseous refrigerant is employed in thesuper-heater device 2| for pre-cooling this circulating air.

Meanwhile, the circulating pump 30 continues to run and serves forheating the air on its way from the evaporator back to the apartment I0,and. for employing usefully the cold withdrawn from this returning airas a means of pre-cooling the air before passing to the evaporator 20,through the agency of the heat exchanger 34.

If this operation of the compressor I6 at fractional capacity is stillinsuiilcient for establishing the desired dehumidication, the sectorsare turned yet further under the control of the hygrostat 50 so that acontact is made at sector 56 for the flowing current by brush 60 andconductor 68 to the control device 69 of the compresser I6 and thelatter cornes into action at full capacity. Thereby a greaterrefrigeration eiect is produced for cooling the air and thusestablishing a very low dew point thereof, together with an eiiicientexchanging of heat between the air at the two stages of its movementthrough the conduit I2.

` It will be noted that the several electrical devices are connectedwith a return conductor 65 to complete the back flow of current.

It is obviousthat if the air becomes drier than a pre-determinedstandard, the hygrostat 50 causes a reverse-operation of the drivingdevice 52 so that the sectors successively open the paths for current totheir correspondingbrushes 60, 59, and 58.

It is obvious that the invention is not limited heat exchange relationwith the air iiowingxinl said path for successively producing a coolingand to the particular employment illustrated, but that it may beemployed in-many ways Within the scope of the appended claims.

Having thus described my invention, what I claim is: a

1. An air conditioning apparatus including means providing a path ofilow for the air; and a refrigerating plant having a compressor, acondenser, a refrigerant liquid subcooler, an expander, an evaporator,and a refrigerant gas l superheater connected together; saidsuperheater, evaporator and sub-cooler being located in heat exchangerelation with the flowing air for successively producing a precooling,cooling and re-.

heating thereof; heat exchanging devices located upstreamward anddownstreamward of the evaporator in said path of air ow, means forcirculating an exchange medium through said heat exchange devices sothat the upstreamward device exerts a cooling eiect upon the flowing airand the downstreamward device exerts a heating effect thereon; saidcooling device, said evaporator and said heating device beingsuccessively traversed by air owing in said path; and means responsiveto the humidity of the iiowing air for controlling the circulationthrough said heat exchanging devices and for varying the output of saidcompressor, said responsive means being effective for establishing amaximum circulation through said heat exchanging devices beforeestablishing a maximum output of said compressor.

2. An air conditioning apparatus including means providing a path of owfor the air, la refrigerating plant including a Variable capacitycompressor and an evaporator, heat exchanging devices locatedupstreamward and downstreamward of the evaporator, means for circulatingan exchange medium through'said heat exchange devices so that theupstreamward device exerts a cooling eiect upon the flowing air and thedownstreamward device exerts a heating elect thereon, said coolingdevice, said evaporator and said heating device being successivelytraversed by air flowing through said means, and means responsive to thehumidity of the' flowing air for controlling the circulation throughsaid devices and for varying the output of said compressor, saidresponsive means being effective for establishing a maximum circulationthrough said heat exchanging devices before establishing a maximumoutput of said compressor.

3. An air conditioning apparatus including means providing a path of owfor the air; and

a refrigerating plant having a compressor, a con-y denser, a refrigerantliquid subcooler, an expander, and an evaporator connected together;said evaporator and subcooler being located in a reheating thereof; heatexchanging devices located upstreamward and downstreamward of theevaporator, means for circulating a heat exchange medium through saidheat exchange devices so that the upstreamward device exerts a coolingeiect upon the flowing air and the downstreamward device exerts, aheating effect thereon, said downstreamward device being located betweenthe evaporator and the sub-cooler; said cooling device, said evaporator,said heating device and said subcooler being successively traversed byair flowing in said path; and means responsive to the humidity of theflowing air for controlling the circulation through said exchangingdevices and for varying the eect of said ble capacity,

evaporator, said responsive means being eiective for establishing amaximum circulation through said heat exchanging devices before securingthe maximum eilects from said sub-cooler and said evaporator. f

4. An air conditioningl apparatus including means providing a path of owfor the air; a refrigerating plant having a compressor, a condenser, arefrigerant liquid subcooler, an expander, an evaporator, and arefrigerant gas superheater connected together; said superheater,evaporator, and subcooler being located in succession downstreamward ofone another in heat exchange relation with the air flowing in said path;a first heat exchange radiator located between the superheater and theevaporator in said path of ow, a second heat exchanger radiator 5. Anair conditioning apparatus including means providing a path of flow forthe air; a refrigerating plant having a compressor, a condenser, anexpander, and an vevaporator connected together, said evaporator beinglocated in heat exchange relation with the air owing in said path; afirst radiator located upstreamward of the evaporator, a secondradiatorlocated downstreamward of the evaporator, and liquid' moving means formaintaining the flow through and between said radiators; a device'responsive to the condition of humidity of the air moving in said path,means controlled by said responsive device for controlling the operationof said liquid moving means for determining the amount of waterseparated from the moving air, and means also controlled by saidresponsive device for changing the refrigerating effect at saidevaporator, said controlled means being coordinately actuated so that amaximum operation of said liquid moving means is produced before amaximum cooling effect is produced in said evaporator.

6. An air conditioning apparatus including means providing a path ofrefrigerating plant having a compressor of variaa condenser, anexpander, and an ow for the air, a

evaporator connected together, said evaporator t by said responsivedevice for successively controlling said liquid moving means and saidcompressor and operating when a minor dehumidication is to beaccomplished for energizing said liquid moving means and operatingwhenqsuccessively greater dehumidifications are to be accomplished forstarting the compressor and for eiecting the operation of the same atfull capacity.

7. An air conditioning apparatus including means providing a path of owfor the air; a refrigerating plant including a compressor of Variablecapacity, an evaporator, and a refrigerant liquid sub-cooler, saidevaporator and subcooler being successively traversed by air owingthrough said means; heat exchanging devices located upstreamward anddownstreamward of the evaporator in the path of the air owingtherethrough, means for circulating an exchange the humidity of theflowing air for controlling medium through said heat exchange device sothe circulation through said heat exchanging dethat the upstreamwarddevice exerts a cooling vices and for varying the output of saidcompreseffect upon the flowing air and the downstreamsor, saidresponsive means being effective for ward device exerts a heating effectthereon; said establishing a maximum circulation through said coolingdevice, said evaporator and said heating 'exchanging devices beforeestablishing a maxl device being successively traversed by air fiowimumoutput of said compressor.

ing through the same; and means responsive to NORMAN H. GAY.

